Amgen CEO: We're not splitting up

A week ago, activist investor Dan Loeb turned a brighter spotlight on Amgen when his firm, Third Point, highlighted its investment in the biotechnology company and made a bold suggestion: that the drugmaker split up.

"It is well‐established that disparate business units generally benefit from operating separately due to distinct corporate cultures, superior efficiencies, and a greater focus for employees and management alike," Third Point said in its Oct. 21 investor letter. "Given the diverse nature of its assets—cash‐generative Mature Products and R&D‐intensive Growth Products—we believe that Amgen could benefit from a separation into distinct operating units with separate financial statements and should seriously consider separating into two companies."

"As we've looked at this, we've not seen a way through we think unlocks significant value for our shareholders," Bradway told analysts and investors Tuesday at Amgen's business review in New York. "What I'm not saying is, 'No, never,' but right now we're not convinced there's a way through that adds value for all of our shareholders."

Robert Galbraith | Reuters

Amgen's stock was trading up more than 4 percent mid-morning.

The company also said it's expanding a restructuring announced earlier this year, and cutting an additional 5 percent of its workforce to make a total reduction of 20 percent. Amgen also detailed plans to pay out about 60 percent of adjusted net income, on average, to shareholders through 2018, increase its dividend by 30 percent in the first quarter of 2015, and buy back about $2 billion in stock through next year.

The company estimated 2015 revenue of $20.8 billion to $21.3 billion, and adjusted earnings of $9.05 to $9.40 a share.